Fuel vaporizer and mixer



March 6, 1928. v 1,661,773

F. A. SMITH FUEL VAPORIZER AND MIXER Filed. D60. 6, 1922 A/ x/ m P M L I I 82, M aui %%ig Patented Mar. 6, 1928.

is .uemrso STATES PATENT OFFICE.

rmx A. smrrrr, or 'IN'AUGATUGK, ooivnnc'rrou'rn FUEL VAPORIZER AND JY IIXER "Application filed December 6, 1922. Serial No. 605,145.,

The invention relates to improvements in devices for mixing with aira'fiuid combusti- 'ble' intended'for use with internal combustion engines; and it has foritsobject a device of this character which will be of simple'and-ru'gged construction, and insure, for example, complete vaporization of a liquid fuel'andefl'ect a thorough mixture of samewithfair. A further object of the invention consists in an arrangement whereby this mixture may be preheated. The invention has forastill further object to dispense with thev'usual type of carburetor which includes a spray or jet device, or the like, for

vaporizing the fuel; I

In accordance with-the invention, the fuel and air supplied to the engine are caused to travel a helical path thru a suitable mixing chamber; and, if desiredthe mixture therein maybe heated'to the desired degree and the air preheated, as by employing the exhaust gases from the engine for this purpose. The liquid fuel maybe supplied thereto in any suitable'manner; but it is preferred to also provide a member afl'ordinga large surface as in providing a helical path for the liquid'fuehthe pathheing of: sutiicient length to insure complete vaporization of the fuel in its travel thru the chamber,

The nature of the invention, however, will best be understood when described in connection with the accompanying drawings, in

which- V Fig. 1 is aview of an internal combustion engine and manifold, showingthe improved vaporizer connected thereto.

Fig. 2 is a similar view illustrating the ap plication thereto of a preheater fort-he m1xture. l

Fig. 3 is an enlarged longitudinal section of a vaporizer of thetype'shown in theembodiment illustrated in Fig.9."

Similar characters of reference designate corresponding parts thruout the several views. a

' "Referring to the drawings, 10 designates a suitable casing, for"examp1e cylindrical in shape, in whichthe air and fuel areto be suitably mixed and vaporized. Oneend of this cylinder is rprovidedwith an-outlet duct .11 designedt'obeconnected tothe inlettmani- 11151111131 COl'ltlOl 1118811181,

fold lZ of the internal combustion engine. A throttlevalve 13 is included in said outlet duct and is operated'in the usual manner to control the supply of the mixture from the cylinder 10 to the engine.

At the opposite end, cylinder 10 isprovided with an inlet duct 14for airyandthe same ispreferably arranged'to be preheated. For this purpose,there is provided over the exhaust manifold 15 of the engine a pipe or stove 16, open at the one end and connected at the other end with the inlet duct 14.

.Air is drawn .in'thru the pipe l6'as the engine is operated, and is thus'heated by-the exhaust gases therefrom in the exhaust manifold and enters the cylinder 10 in this condition. A combustible fuel as a liquid fuel may be fed in any suitable manner thru a supply pipe 17 to the said cylinder 10, thru a suitable inlet or needle valve 18, having well understood; t v In Figs. 2 and 3, an arrangementris disclosed wherein the airis similarly preheated but the exhaust pipe 15, also, isarra-nged to pass axially thru the cylinder 10 and thus serves to heat the mixture within the cylinder. In order to efiect a complete mixture of the liquid fuel and air supplied to the cylinreadily accessible as is der 10, the mixture is caused, to travel a helical path thru the cylinder, dividing walls 20 being provided to this end thru the cylinder inhelical arrangement; and in the emably of' twisted sheet metal but may .be of various other constructions, as will .be ,apparent to those skilled inthe art; ,and the mixture may or may not/be preheated'as set forth, and directly or,indirectly fromthe for this purpose from exhaust pipe of the engine. Thus, the cylinder 10 may be placed against the engine exhaust or within or about same.

It is preferred, moreover, to force the liquid fuel to similarly take an elongated and tortuous path thru the cylinderand to provide a considerable surface for its vaporization. To this end, the liquid fuel, which may be fed by gravity, pressure or vacuum in the usual manner, is intfoduced to the cylinder 10 thru the suitably controlled needle valve 18, and is directed to the axis of the said cylinder by a tube 21. Within the tube is provideda ribbon22 of twisted metal which extends therefrom and is carried along and wound over the exhaust pipe 15, following the convolutions of the helical walls 20 so that-the liquid fuel travels along said band and likewise helically toward the outlet;duct. Thistendency of the fuel to cling to the ribbon of twisted metal is probably due to surface adhesion and the action of the moving column of air thru the passageway, as well as to the fact that the weight of liquid per unit of surface is continuously decreasing as the fuel advances along the ribbon, the liquid finally completely disappearing therefrom when vaporized; Moreover, the ribbon 22 is so placed as to be in contact with the hot exhaust pipe 15, which further serves to effectvaporization of'the fuel passing over the band.

It will be understood that the proper proportions of air and liquid fuel will be supplied and maintained in the usual manner y suitable and well-known devices which form no part of the present invention, which relates solely to the novel form of vaporizer and mixer hereinbefore described. The same comprises essentially a casing for receiving air and liquid fuel thru which a mixture thereof is caused to flow inn helical path, the air being-preheated, if desirable, as may also be the entire mixture, and the heat being obtained directly or indirectly the exhaust gases of the engine to be supplied with and operated by the gaseous mixture.

. I claim 1. A vaporizer for liquid fuel for internal combustion engines, comprising a tubular casing forming a chamber and having inlets at one end respectively for air and fuel and an outlet at the other end fora mixture thereof, a helical member disposed in said cham ber between the inlet and the outlet thereof to provide with the casing and thruout its entire length a helical passageway of continuous and smooth surface to insure against pocketing thereby of any fuel, said passageway being adapted to directthe air therethru in a whirling movement and to effect a mixture of the same with the fuel, the inlet for the fuel being on the engine side of the inlet for the air and both air and fuel passing thru the vaporizer in the same direction, means to direct the fuel in liquid form into the said passageway substantially in the longitudinal axis thereof, and a band of metal substantially in the longitudinal axis ofthe helical member and following its convolutions and adapted to receive said fuel. e

2. A vaporizer for liquid fuel for internal combustion engines, comprising a tubular casing forming a chamber and having inlets at one end respectively for air and fuel and anoutlet at the other end for a mixture thereof, a helical member disposed in said chamber between the inlet and the outlet there" of to provide with the casing and thruout its entire length a helical passageway of con tinuous and smooth surface to insure against pocketing thereby of any fuel, said passageway being adapted to direct the air therethru in a whirling movement and to effect a mixture of the same with the fuel, the inlet for the fuel being on the engine side of the inlet for the airand both air and fuel passing thru the vaporizer in the same direction, and a band of metal extending into the fuel inlet to act as a guide for the fuel from the said fuel inlet substantially cenitlrally of the convolutions of the helical mem- 8. A vaporizer for liquid fuel for internal combustion engines comprising a tubular casing forming a chamber and having inlets at one end respectively for air and fuel and an outlet at the other end for a n'iixture thereof, a helical member disposed in said chamber between the inlet and the outlet thereof to provide with the casing and thruout-its entirolength ahelical passageway of continuous and smooth surface to insure against pocketing thereby of any fuel, said passageway being adapted to direct the air therethru in a whirling movementand to effect a mixture of the same with the fuel, the inlet for the fuel being on the engine side of the inlet for the air and both air and fuel passing thru the vaporizer in the same direction, a tube passing axially thru the casing and helical member to receive the exhaust from the engine, and a band of metal twisted about said axial tube, following the convolutions of the helical member and smooth surfaee'to passageway to act as a guidefol' the fuel from the said inlet to the convolutions of 10v the said helical member.

Signed at Naugatuck, in the county of New Haven, and State of Connecticut, this 27th day of November, A. D. 1922.

FRANK A. SMITH. 

